Surgical forceps

ABSTRACT

An end effector of a forceps includes first and second jaw members movable between spaced-apart and approximated positions for grasping tissue. Each jaw member includes a tissue sealing plate that is selectively energizable. The tissue sealing plates are configured to conduct energy therebetween and though tissue to seal tissue. A knife includes a distal surface and an upper surface. The knife is selectively translatable between a retracted position and an extended position wherein the knife extends between the jaw members. The distal surface is configured for dynamic tissue cutting upon translation of the knife from the retracted to the extended position. The upper surface is configured for static tissue cutting with the knife in the extended position. The knife is selectively energizable and is configured to conduct energy between the knife and one or both of the tissue sealing plates and through tissue to electrically cut tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patent application Ser. No. 13/293,754, filed on Nov. 10, 2011, the entire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical instruments and, more particularly, to surgical forceps for grasping, sealing and/or dissecting tissue.

2. Background of Related Art

A forceps is a plier-like instrument which relies on mechanical action between its jaws to grasp, clamp and constrict vessels or tissue. Electrosurgical forceps utilize both mechanical clamping action and electrical energy to affect hemostasis by heating tissue and blood vessels to coagulate and/or cauterize tissue. Certain surgical procedures require more than simply cauterizing tissue and rely on the unique combination of clamping pressure, precise electrosurgical energy control and gap distance (i.e., distance between opposing jaw members when closed about tissue) to “seal” tissue, vessels and certain vascular bundles.

Typically, once a vessel is sealed, the surgeon has to accurately sever the vessel along the newly formed tissue seal. Accordingly, many vessel sealing instruments have been designed which incorporate a knife or blade member that effectively severs the tissue after forming a tissue seal. In certain instances, it may be necessary to dissect, or cut through tissue in order to reach an underlying vessel (or vessels), or for other purposes.

SUMMARY

As used herein, the term “distal” refers to the portion that is being described which is further from a user, while the term “proximal” refers to the portion that is being described which is closer to a user. The terms “knife” and “tissue-cutting surface,” as used herein, do not necessarily mean a component, or portion thereof, that includes a sharp cutting edge for mechanical cutting. Rather, “knife” and “tissue-cutting surface” are used herein to more generally refer to those components, or portions thereof, that are used to cut tissue, e.g., a blunt component or surface for electrical tissue cutting, an edge or corner to facilitate electrical tissue cutting, a sharpened component or surface for mechanical tissue cutting, or combinations thereof.

Any of the aspects described herein, to the extent consistent, may be used in conjunction with any of the other aspects described herein.

In accordance with one aspect of the present disclosure, a forceps is provided. The forceps includes an end effector assembly having first and second jaw members. One or both of the jaw members is movable relative to the other between a spaced-apart position and an approximated position for grasping tissue therebetween. Each jaw member includes an electrically-conductive tissue sealing plate that is adapted to connect to a source of energy. The tissue sealing plates are selectively energizable independently of one another and are configured to conduct energy therebetween and though tissue to seal tissue. A knife includes a distal tissue-cutting surface and an upper tissue-cutting surface. The knife is selectively translatable relative to the jaw members between a retracted position and an extended position, wherein the knife extends between the jaw members. The distal tissue-cutting surface is configured for dynamic tissue cutting upon translation of the knife from the retracted position to the extended position. The upper tissue-cutting surface is configured for static tissue cutting when the knife is disposed in the extended position. The knife is adapted to connect to the source of energy and is selectively energizable independently of the tissue sealing plates. The knife is configured to conduct energy between the knife and one or both of the tissue sealing plates and through tissue to electrically cut tissue.

In one aspect, a handle assembly is provided for selectively moving the jaw members between the spaced-apart and approximated positions.

In another aspect, a trigger assembly is provided for selectively translating the knife between the retracted and extended positions.

In another aspect, a first activation switch is provided for selectively energizing the tissue sealing plate of the first jaw member and a second activation switch is provided for selectively energizing the tissue sealing plate of the second jaw member.

In yet another aspect, a knife actuation switch is provided for selectively energizing the knife.

In still another aspect, the knife and the tissue sealing plates of the first and second jaw members are energizable to conduct energy therebetween and through tissue to electrically cut tissue when the knife is translated between the retracted and extended positions.

In still yet another aspect, the knife and the tissue sealing plate of the second jaw member are energizable to conduct energy therebetween and through tissue to electrically cut tissue via tenting when the jaw members are disposed in the spaced-apart position and the knife is disposed in the extended position.

In another aspect, the knife and the tissue sealing plate of the first jaw member are energizable to conduct energy therebetween and through tissue to electrically cut tissue via scissor-cutting.

In another aspect, one or more insulators are disposed between the knife and the tissue sealing plates. The insulators are configured to inhibit contact between the knife and the tissue sealing plates.

A method of surgery is also provided in accordance with the present disclosure. The method includes providing a forceps having an end effector assembly including first and second jaw members. Each jaw member includes an electrically-conductive tissue sealing plate adapted to connect to a source of energy. A knife is selectively translatable between the first and second jaw members. The method further includes moving the jaw members to an approximated position relative to one another to grasp tissue therebetween, energizing the tissue sealing plate of one (or both) of the first and second jaw members to seal tissue grasped between the jaw members, moving the jaw members to a spaced-apart position relative to one another, deploying the knife between the jaw members, overlaying the tissue seal across an upper edge of the knife, and moving the end effector assembly transversely relative to tissue to cut tissue via tenting.

In one aspect, the knife is adapted to connect to the source of energy. In such an aspect, the knife may be energized to electrically cut tissue via tenting. The forceps may further include a knife actuation switch for selectively energizing the knife.

In another aspect, the forceps includes a trigger assembly for selectively deploying the knife between the jaw members, e.g., for translating the knife between a retracted position and an extended position.

In yet another aspect, the forceps includes a handle assembly for moving the jaw members between the spaced-apart position and the approximated position.

In still another aspect, the forceps includes a first activation switch for selectively energizing the tissue sealing plate of the first jaw member and a second activation switch for selectively energizing the tissue sealing plate of the second jaw member.

A method of surgery provided in accordance with another aspect of the present disclosure includes providing a forceps according to any of the above aspects. The method further includes moving the jaw members to an approximated position relative to one another to grasp tissue therebetween, energizing the tissue sealing plate of one (or both) of the first and second jaw members to seal tissue grasped between the jaw members, opening the jaw members relative to one another, deploying the knife between the jaw members, positioning the tissue seal between the jaw members, and moving the jaw members from the spaced-apart position to the approximated position to scissor-cut tissue along the tissue seal.

In one aspect, the knife is adapted to connect to the source of energy. In such an aspect, the knife may be energized to electrically scissor-cut tissue. The forceps may further include a knife actuation switch for selectively energizing the knife.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are described in detail with reference to the drawing figures wherein like reference numerals identify similar or identical elements:

FIG. 1 is a front, perspective view of an endoscopic surgical forceps configured for use in accordance with the present disclosure;

FIG. 2 is a front, perspective view of an open surgical forceps configured for use in accordance with the present disclosure;

FIG. 3 is an enlarged, front, perspective view of an end effector assembly configured for use with the forceps of FIG. 1 or 2;

FIG. 4 is a perspective view of a knife assembly configured for use with the forceps of FIG. 1 or 2;

FIG. 5A is a longitudinal, cross-sectional view of the end effector assembly of FIG. 3, wherein the jaw members are shown in a spaced-apart position and wherein the knife assembly is shown in a retracted position;

FIG. 5B is a longitudinal, cross-sectional view of the end effector assembly of FIG. 3, wherein the jaw members are shown in an approximated position and wherein the knife assembly is shown in the retracted position;

FIG. 5C is a longitudinal, cross-sectional view of the end effector assembly of FIG. 3, wherein the jaw members are shown in an approximated position and wherein the knife assembly is shown in an extended position;

FIG. 6A is a front, perspective view of the end effector assembly of FIG. 3, wherein the jaw members are shown in the spaced-apart position and wherein the knife assembly is shown in the extended position;

FIG. 6B is a front, perspective view of the end effector assembly of FIG. 3, wherein the jaw members are in the spaced-apart position and the knife assembly is in the extended position to dissect tissue;

FIG. 7A is a side view of the end effector assembly of FIG. 3, wherein the jaw members are shown in the spaced-apart position and wherein the knife assembly is shown in the extended position; and

FIG. 7B is a side view of the end effector assembly of FIG. 3, wherein the jaw members are shown moving towards the approximated position and wherein the knife assembly is shown in the extended position.

DETAILED DESCRIPTION

Referring now to FIGS. 1 and 2, FIG. 1 depicts a forceps 10 for use in connection with endoscopic surgical procedures and FIG. 2 depicts an open forceps 10′ contemplated for use in connection with traditional open surgical procedures. For the purposes herein, either an endoscopic instrument, e.g., forceps 10, or an open instrument, e.g., forceps 10′, may be utilized in accordance with the present disclosure. Obviously, different electrical and mechanical connections and considerations apply to each particular type of instrument; however, the novel aspects with respect to the end effector assembly and its operating characteristics remain generally consistent with respect to both the open and endoscopic configurations.

Turning now to FIG. 1, an endoscopic forceps 10 is provided defining a longitudinal axis “X-X” and including a housing 20, a handle assembly 30, a rotating assembly 70, a trigger assembly 80, and an end effector assembly 100. Forceps 10 further includes a shaft 12 having a distal end 14 configured to mechanically engage end effector assembly 100 and a proximal end 16 that mechanically engages housing 20. Forceps 10 also includes electrosurgical cable 610 that connects forceps 10 to a generator (not shown) or other suitable power source, although forceps 10 may alternatively be configured as a battery powered instrument. Cable 610 includes wires (not shown) extending therethrough that has sufficient length to extend through shaft 12 in order to provide electrical energy to at least one of the sealing plates 112, 122 of jaw members 110, 120, respectively, of end effector assembly 100, e.g., upon activation of activation switch 90.

With continued reference to FIG. 1, handle assembly 30 includes a fixed handle 50 and a moveable handle 40. Fixed handle 50 is integrally associated with housing 20 and movable handle 40 is moveable relative to fixed handle 50. Rotating assembly 70 is rotatable in either direction about longitudinal axis “X-X” to rotate end effector 100 about longitudinal axis “X-X.” Housing 20 houses the internal working components of forceps 10.

End effector assembly 100 is shown attached at a distal end 14 of shaft 12 and includes a pair of opposing jaw members 110, 120. Each of the jaw members 110, 120 includes an electrically-conductive tissue sealing plate 112, 122, respectively. End effector assembly 100 is designed as a unilateral assembly, e.g., where jaw member 120 is fixed relative to shaft 12 and jaw member 110 is moveable relative to shaft 12 and fixed jaw member 120 (although the reverse configuration is also contemplated). However, end effector assembly 100 may alternatively be configured as a bilateral assembly, i.e., where both jaw member 110 and jaw member 120 are moveable relative to one another and to shaft 12. A knife assembly 180 (FIGS. 4-5C) is disposed within shaft 12 and a knife channel 115, 125 (FIGS. 5A-5C) is defined within one or both jaw members 110, 120 to permit reciprocation of a knife 184 (FIGS. 4-5C) therethrough, e.g., via actuation of a trigger 82 of trigger assembly 80. The particular features of end effector assembly 100 and knife assembly 180 (FIGS. 4-5C) will be described in greater detail hereinbelow.

Continuing with reference to FIG. 1, moveable handle 40 of handle assembly 30 is ultimately connected to a drive assembly (not shown) that, together, mechanically cooperate to impart movement of jaw members 110, 120 between a spaced-apart position and an approximated position to grasp tissue disposed between sealing plates 112, 122 of jaw members 110, 120, respectively. As shown in FIG. 1, moveable handle 40 is initially spaced-apart from fixed handle 50 and, correspondingly, jaw members 110, 120 are in the spaced-apart position. Moveable handle 40 is movable from this initial position to a depressed position to move jaw members 110, 120 to the approximated position for grasping tissue therebetween (see FIGS. 5B-5C).

Referring now to FIG. 2, an open forceps 10′ is shown including two elongated shafts 12 a, 12 b, each having a proximal end 16 a, 16 b and a distal end 14 a, 14 b, respectively. Similar to forceps 10 (FIG. 1), forceps 10′ is configured for use with end effector assembly 100. More specifically, end effector assembly 100 is attached to distal ends 14 a, 14 b of shafts 12 a, 12 b, respectively. As mentioned above, end effector assembly 100 includes a pair of opposing jaw members 110, 120 that are pivotably coupled to one another. Each shaft 12 a, 12 b includes a handle 17 a, 17 b disposed at the proximal end 16 a, 16 b thereof. Each handle 17 a, 17 b defines a finger hole 18 a, 18 b therethrough for receiving a finger of the user. As can be appreciated, finger holes 18 a, 18 b facilitate movement of shafts 12 a, 12 b relative to one another which, in turn, pivots jaw members 110, 120 from an open position, wherein jaw members 110, 120 are disposed in spaced-apart relation relative to one another, to a closed position, wherein jaw members 110, 120 cooperate to grasp tissue therebetween.

A ratchet 30′ may be included for selectively locking jaw members 110, 120 relative to one another at various positions during pivoting. Ratchet 30′ may include graduations or other visual markings that enable the user to easily and quickly ascertain and control the amount of closure force desired between jaw members 110, 120.

With continued reference to FIG. 2, one of the shafts, e.g., shaft 12 b, includes a proximal shaft connector 19 that is designed to connect forceps 10′ to a source of electrical energy such as an electrosurgical generator (not shown). Proximal shaft connector 19 secures an electrosurgical cable 610′ to forceps 10′ such that the user may selectively apply electrosurgical energy to electrically-conductive tissue sealing plates 112, 122 of jaw members 110 and 120, respectively, as needed.

Forceps 10′ may further include a knife assembly 180 (FIGS. 4-5C) disposed within either of shafts 12 a, 12 b and a knife channel 115, 125 (FIGS. 5A-5C) defined within one or both of jaw members 110, 120, respectively, to permit reciprocation of a knife 184 (FIGS. 5-8C) therethrough.

Turning now to FIG. 3, end effector assembly 100, including jaw members 110, 120 is configured for use with either forceps 10 or forceps 10′, discussed above, or any other suitable surgical instrument capable of pivoting jaw members 110, 120 relative to one another between a spaced-apart position and an approximated position for grasping tissue therebetween. However, for purposes of simplicity and consistency, end effector assembly 100 will be described hereinbelow with reference to forceps 10 only.

Jaw members 110, 120, as shown in FIG. 3, each include an outer, insulative jaw housing 111, 121 and an electrically-conductive tissue sealing plate 112, 122 disposed atop respective jaw housings 111, 121 in opposed relation relative to one another. Tissue sealing plates 112, 122 are adapted to connect to a source of electrical energy, e.g., electrosurgical energy, independently of one another such that, as will be described in detail below, either or both of tissue sealing plates 112, 122 may be selectively energized, depending on a particular purpose. Activation switch 90 (FIG. 1) is selectively actuatable to control the supply of energy to tissue sealing plates 112, 122. More specifically, activation switch 90 (FIG. 1) may include first and second switch components 90 a, 90 b (FIG. 1) to facilitate selective activation of either or both of tissue sealing plates 112, 122.

One or both of jaw members 110, 120 includes a longitudinally-extending knife channel 115, 125 (FIGS. 5A-5C) that, as mentioned above, is configured to permit reciprocation of a knife 184 (FIGS. 4-5C) therethrough. An insulator 124 lines each of knife channels 115, 125 to electrically isolate knife 184 (FIG. 4) from tissue sealing plates 112, 122.

Turning now to FIG. 4, knife assembly 180 generally includes a knife 184 and a knife bar 186. Knife 184 is coupled to a knife bar 186 at the proximal end 185 of knife 184 and extends distally from knife bar 186 to define a tissue-cutting portion 188 at the distal end 187 thereof. Tissue-cutting portion 188 of knife 184 defines both a distal tissue-cutting surface 189 a to facilitate cutting of tissue as knife 184 is translated longitudinally relative to tissue and an upper tissue-cutting surface 189 b extending along the length of tissue-cutting portion 188 to facilitate cutting of tissue as knife 184 is translated transversely relative to tissue. Tissue-cutting surfaces 189 a, 189 b may define sharpened-blade configurations, dull-blade configurations, blunt configurations, or combinations thereof (e.g., distal tissue-cutting surface 189 a may define a sharpened-blade, while upper tissue-cutting surface 189 b defines a blunt configuration, although the reverse configuration or other configurations are also contemplated). Further, tissue-cutting surfaces 189 a, 189 b may define various different edge or corner configurations to concentrate electrical current and facilitate electrical cutting of tissue.

With continued reference to FIG. 4, knife 184 is coupled to a source of energy, e.g., electrosurgical energy, via lead wire 183. Lead wire 183 extends from knife 184 proximally through shaft 12 (FIG. 1), ultimately coupling to a source of energy, e.g., to a portable generator (not shown) disposed within housing 20 (for battery-powered instruments), or to an external generator (not shown) via cable 610 (FIG. 1). A knife activation switch 92 (FIG. 1) disposed on housing 20 (FIG. 1) is selectively activatable to energize knife 184, e.g., to control the supply of energy from lead wire 183 to knife 184.

Turning now to FIGS. 1, 3, and 5A-7B, end effector assembly 100 is configured to operate in various different modes and to transition efficiently between the various different modes of operation. As such, end effector assembly 100 is capable of performing a variety of surgical tasks without requiring the use of additional instrumentation and without requiring withdrawal of end effector assembly 100 to transition end effector assembly 100 to a different mode of operation. In particular, end effector assembly 100 is configured at least for: grasping tissue between jaw members 110, 120; sealing tissue grasped between jaw members 110, 120; mechanically cutting tissue grasped between jaw members 110, 120; electrically/electromechanically cutting tissue grasped between jaw members 110, 120; mechanically cutting tissue with jaw members 110, 120 disposed in the spaced-apart position; electrically/electromechanically cutting tissue with jaw members 110, 120 disposed in the spaced-apart position; mechanically scissor-cutting tissue; and electrically/electromechanically scissor-cutting tissue. Each mode of operation is described in detail below.

Referring to FIGS. 1, 3 and 5A-5C, the use of end effector assembly 100 for grasping, sealing, and/or cutting tissue, e.g., mechanically, electrically, or electromechanically cutting tissue, grasped between jaw members 110, 120 is described. Initially, with jaw members 110, 120 disposed in the spaced-apart position (FIG. 5A), end effector assembly 100 is maneuvered into position such that tissue to be grasped, sealed, and/or cut is disposed between jaw members 110, 120. Next, moveable handle 40 is pulled proximally relative to fixed handle 50 such that jaw member 110 is pivoted relative to jaw member 120 from the spaced-apart position to the approximated position to grasp tissue between tissue sealing plates 112, 122 of jaw members 110, 120, respectively (FIG. 5B). Thereafter, energy may be supplied, e.g., via activation of activation switch 90 to tissue sealing plate 112 and/or tissue sealing plate 122 and conducted through tissue to effect a tissue seal. For example, tissue sealing plate 112 of jaw member 110 may be energized to a first potential, e.g., via activation of first switch component 90 a, while tissue sealing plate 122 of jaw member 120 is energized to a second potential different from the first (or is not energized), e.g., via activation of second switch component 90 b, thus creating a potential difference between tissue sealing plates 112, 122 such that energy is conducted therebetween and through tissue to effect a tissue seal. That is, in this configuration, tissue sealing plate 112 functions as the “active” electrode, while tissue sealing plate 122 functions as the “return” electrode. Other configurations for sealing tissue are also contemplated, e.g., wherein tissue sealing plate 122 is the “active” electrode and wherein tissue sealing plate 112 is the “return” electrode.

Once tissue sealing is complete (or where only grasping and cutting is desired), knife 184 may be advanced from the retracted position (FIG. 5B) to the extended position (FIG. 5C), e.g., via activation of trigger 82, such that knife 184 is translated through knife channels 115, 125 of jaw members 110, 120, respectively, to cut tissue grasped between jaw members 110, 120. As knife 184 is translated distally though knife channels 115, 125 of jaw members 110, 120, respectively, distal tissue-cutting portion 189 a of knife 184 mechanically cuts or dissects tissue grasped between jaw members 110, 120.

Continuing with reference to FIGS. 1, 3 and 5A-5C, knife 184 may be energized as knife 184 is advanced through jaw members 110, 120 to facilitate cutting of tissue. More specifically, knife activation switch 92 may be activated to supply energy to knife 184 (the “active” electrode), via lead wire 183 (FIG. 4), for electrically/electromechanically cutting tissue grasped between jaw members 110, 120. In this mode, tissue sealing plates 112, 122 are not energized (or are energized to a different potential from knife 184), thus functioning as the “return” electrode. In use, as the energized knife 184 is translated through jaw members 110, 120, energy is conducted between distal tissue-cutting surface 189 a and tissue sealing plates 112, 122 and through tissue therebetween to electrically cut tissue, while the advancement of distal tissue-cutting surface 189 a through tissue mechanically cuts tissue. This conduction of energy through tissue for electrical cutting also results in some coagulation of tissue adjacent the cut line. Insulators 124 lining knife channels 115, 125 of jaw members 110, 120, respectively, inhibit contact between knife 184 and tissue sealing plates 112, 122 as knife 184 is translated therethrough, thus inhibiting shorting of the electrodes.

The particular mode of end effector assembly 100, e.g., grasping, tissue sealing, mechanical tissue cutting, and/or electrical tissue cutting, used for sealing and/or dividing tissue, may depend on the size and/or composition of tissue, the procedure to be performed, other anatomical considerations, etc. For example, for certain tissue, e.g., more avascular tissue, or where rapid dissection is required, it may be sufficient to grasp tissue between jaw members 110, 120, energize knife 184, and advance knife 184 between jaw members to electrically cut tissue, while the coagulation adjacent the cut line sufficiently reduces bleeding. For other tissue, e.g., more vascular tissue, or where rapid dissection is not as important, tissue may be grasped and sealed prior to advancement of knife 184 to cut tissue along the tissue seal. In this mode, the size and/or composition of tissue, or other factors, may dictate whether mechanical cutting or electrical/electromechanical cutting is required.

With reference to FIGS. 1, 3 and 6A-6B, the use of end effector assembly 100 for open-jaw tissue cutting, e.g., wherein jaw members 110, 120 are disposed in the spaced-apart position, is described. As mentioned above, knife 184 includes an upper tissue-cutting surface 189 b extending along the length of tissue-cutting portion 188 of knife 184. Thus, with jaw members 110, 120 disposed in the spaced-apart position and with knife 184 in the extended position, upper tissue-cutting surface 189 b is exposed such that end effector assembly 100 may be advanced transversely through tissue to cut tissue using upper tissue-cutting surface 189 b of knife 184.

In use, with jaw members 110, 120 disposed in the spaced-apart position, end effector assembly 100 is moved into positioned adjacent tissue to be cut. At this point, or prior to, knife 184 is advanced to the extended position, e.g., via activation of trigger 82 of trigger assembly 80. Knife 184 is retained in the extended position via maintaining trigger 82 in an activated, or depressed position, although trigger assembly 80 may also include a locking mechanism (not explicitly shown) for selectively locking knife 184 in the extended position. In the mechanical cutting mode, with knife 184 in the extended position, end effector assembly 100 is advanced transversely relative to tissue to mechanically cut tissue using upper tissue-cutting surface 189 b of knife 184, as shown in FIG. 6B.

In the electrical/electromechanical cutting mode, knife 184 is energized during open-jaw tissue cutting to facilitate cutting of tissue. More specifically, knife activation switch 92 may be activated to supply energy to knife 184 (the “active” electrode) via lead wire 183 (FIG. 4) for electrically/electromechanically cutting tissue grasped between jaw members 110, 120. In this configuration, tissue sealing plate 112 is not energized. Tissue sealing plate 122 is energized to a different potential from that of knife 184, e.g., via activation of second switch component 90 b, such that tissue sealing plate 122 functions as the “return” electrode. Insulator 124 lining knife channel 125 of jaw member 120 inhibits contact between knife 184 and tissue sealing plate 122, thus inhibiting shorting of the electrodes.

Continuing with reference to FIGS. 1, 3 and 6A-6B, with knife 184 energized as the “active” electrode and with tissue sealing plate 122 energized as the “return” electrode, end effector assembly 100 may be advanced transversely through tissue to electrically/electromechanically cut tissue disposed between jaw members 110, 120 via tenting. Tenting, as shown in FIG. 6B, involves positioning end effector assembly 100 such that tissue to be cut lays over upper tissue-cutting surface 189 b of knife 184 and extends toward jaw member 120 on either side of knife 184 to contact tissue sealing plate 122 of jaw member 120, thus forming a tent-like configuration. In this configuration, tissue contacts upper tissue-cutting surface 189 b of knife 184 at the apex of the tent and tissue sealing plate 122 on the sides of the tent such that energy is conducted from knife 184, through tissue, to tissue sealing plate 122 to electrically cut tissue, while upper tissue-cutting surface 189 b is advanced through tissue to mechanically cut tissue. The transverse translation of end effector assembly 100 relative to tissue during cutting, i.e., the urging of upper tissue-cutting surface 189 b of knife 184 into tissue, helps maintain sufficient tension on tissue and helps ensure contact of tissue with tissue sealing plate 122 on either side of knife 184, thus facilitating the cutting of tissue as end effector assembly 100 is translated transversely therethrough.

It has been found that proper knife height is important in order to achieve optimal tenting. A knife height that is too small may not sufficiently tension tissue, making it more difficult to cut through tissue and insufficiently defining an energy path through tissue. On the other hand, a knife height that is too large may result in too much tenting, e.g., where tissue does not contact or does not sufficiently contact tissue sealing plate 122, reducing the effective current path through tissue between knife 184 and tissue sealing plate 122. Further, the sides of knife 184 may be coated with a dielectric, e.g., silicone, kapton, or any other suitable dielectric, to concentrate energy at upper tissue tissue-cutting surface 189 b of knife 184, thus creating a more defined current path through tissue to tissue sealing plate 122 during cutting. This dielectric coating is also advantageous when end effector assembly 100 is used in the grasping and electrical/electromechanical tissue mode (see FIGS. 5A-5C) or the electrical/electromechanical scissor-cutting mode (see FIGS. 7A-7B), e.g., the dielectric coating facilitates the concentration of energy at the tissue-cutting surface (distal tissue-cutting surface 189 a, for the grasping and electrical/electromechanical tissue mode, or upper tissue-cutting surface 189 b, for the electrical/electromechanical scissor-cutting mode) of knife 184, thus creating a more defined current path through tissue.

The open-jaw tissue cutting mode (e.g., both the mechanical open-jaw cutting mode and the electrical/electromechanical open-jaw cutting mode) of end effector assembly 100 is particularly advantageous where rapid or repeated tissue cutting (without tissue sealing) is required, e.g., for providing access to underlying tissue. For example, the open-jaw tissue cutting mode allows end effector assembly 100 to continuously cut and advance through tissue (e.g., multiple layers of tissue) in order to efficiently and expediently access underlying tissue or an underlying surgical site. Certain tissue, e.g., smaller-diametered tissue, may be cut using mechanical cutting, while other tissue, e.g., stronger or larger tissue, may necessitate the use of tenting and electrical/electromechanical cutting.

With reference to FIGS. 1, 3 and 7A-7B, the use of end effector assembly 100 for mechanically or electro-mechanically scissor-cutting tissue is described. As mentioned above, knife 184 includes an upper tissue-cutting surface 189 b extending along the length of tissue-cutting portion 188 of knife 184. Thus, with jaw members 110, 120 disposed in the spaced-apart position and with knife 184 in the extended position, upper tissue-cutting surface 189 b is exposed. Accordingly, jaw members 110, 120 may be repeatedly moved between the spaced-apart and approximated positions in scissor-like fashion, e.g., via repeatedly squeezing and releasing moveable handle 40, to mechanically cut tissue disposed between jaw members 110, 120. More specifically, in use, tissue is positioned between jaw members 110, 120 such that, as jaw members 110, 120 are moved from the spaced-apart position to the approximated position, upper tissue-cutting surface 189 b of knife 184 is translated through tissue positioned therebetween and into knife channel 115 (FIGS. 5A-5C) of jaw member 110 to cut tissue, while tissue is held in position between jaw members 110, 120.

With continued reference to FIGS. 1, 3 and 7A-7B, end effector assembly 100 may also be used to electromechanically scissor-cut tissue. For electromechanical scissor-cutting, knife 184 is energized, e.g., via activation of knife activation switch 92, to function as the “active” electrode, while tissue sealing plate 112 is energized to a different potential, e.g., via activation of first switch component 90 a, such that tissue sealing plate 112 functions as the “return” electrode. In this configuration, tissue sealing plates 122 is not energized.

In use, in the electrical/electromechanical scissor-cutting mode, tissue is positioned between jaw members 110, 120 and jaw members 110, 120 are moved from the spaced-apart position to the approximated position. As jaw members 110, 120 are moved towards the approximated position, some mechanical cutting is achieved as upper tissue tissue-cutting surface 189 b of knife 184 is urged into tissue positioned between knife 184 and knife channel 115 (FIGS. 5A-5C) of jaw member 110. As jaw members 110, 120 are moved further towards the approximated position, knife 184 and jaw members 110 urge tissue into contact with tissue sealing plate 122 of jaw member 120, to create a current path through tissue from upper tissue-cutting surface 189 b of knife 184 to tissue sealing plate 122, thus allowing conduction of energy therebetween to electrically cut tissue.

The scissor-cutting mode (e.g., both the mechanical and electrical/electromechanical scissor-cutting mode) of end effector assembly 100 is particularly advantageous for cutting stronger and/or lager tissue in that jaw members 110, 120 retain tissue in position as knife 184 is advanced therethrough. The particular procedure, size and/or composition of tissue, or other factors may dictate whether mechanical cutting is sufficient or whether electrical/electromechanical cutting is necessary.

With reference to FIGS. 1-7B, as detailed above, end effector assembly 100 is configured for use in various modes of operation depending on the position of jaw members 110, 120 (as controlled by movable handle 40) and/or knife 184 (as controlled by trigger assembly 80), and the energization of tissue sealing plates 112, 122 (as controlled by first and second switch components 90 a, 90 b, respectively) and/or knife 184 (as controlled by knife activation switch 92). End effector assembly 100 is efficiently transitionable between these various different modes by controlling movable handle 40, trigger assembly 80, first and second switch components 90 a, 90 b, and/or knife activation switch 92. As such, end effector assembly 100 may not only be used for performing various different surgical procedures, but may also be transitioned between two or more of the above-described modes during the course of a single procedure. For example, end effector assembly 100 may be used to mechanically or electrically/electromechanically cut tissue in the open-jaw cutting mode or scissor cutting mode in order to reach underlying tissue to be sealed and/or divided. End effector assembly 100 may then be used to grasp, seal, and divide (mechanically or electrically/electromechanically) the underlying tissue. Alternatively, end effector assembly 100 may be used to grasp and seal tissue, followed by mechanically or electrically/electromechanically cutting tissue along the tissue seal via moving jaw members 110, 120 to the approximated position, advancing knife 184 between jaw members 110, 120, and cutting tissue (mechanically or electrically/electromechanically) along the tissue seal via tenting or scissor-cutting. However, end effector assembly 100 is not limited to these examples (or any specific combination of modes), but, rather, end effector assembly 100 may be transitioned between any of the above-described modes in any suitable order, i.e., end effector assembly 100 may be specifically tailored to perform a desired surgical procedure.

From the foregoing and with reference to the various figure drawings, those skilled in the art will appreciate that certain modifications can also be made to the present disclosure without departing from the scope of the same. While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. 

What is claimed is:
 1. A surgical instrument, comprising: an end effector assembly, including: first and second jaw members, at least one of the first and second jaw members movable relative to the other between a spaced-apart position and an approximated position for grasping tissue therebetween, at least one of the first and second jaw members defining an electrically-conductive surface adapted to connect to a source of energy; and a knife adapted to connect to a source of energy and selectively translatable relative to the first and second jaw members between a retracted position and an extended position wherein the knife extends between the first and second jaw members, the knife translatable between the retracted and extended positions in each of the spaced-apart and approximated positions of the first and second jaw members, the knife configured for dynamic tissue cutting upon translation of the knife from the retracted position to the extended position with the first and second jaw members disposed in the approximated position, the knife configured for static tissue cutting with the knife disposed in the extended position.
 2. The surgical instrument according to claim 1, wherein the knife is configured for static tissue cutting with the knife disposed in the extended position and the first and second jaw members disposed in the spaced-apart position.
 3. The surgical instrument according to claim 1, wherein the knife is configured for static tissue cutting with the knife disposed in the extended position and the first and second jaw members moving between the spaced-apart and approximated positions.
 4. The surgical instrument according to claim 1, further including a handle assembly operably associated with the end effector assembly, the handle assembly including a movable handle selectively actuatable for moving the first and second jaw members from the spaced-apart position to the approximated position.
 5. The surgical instrument according to claim 1, further including a trigger assembly operably associated with the knife, the trigger assembly including a trigger selectively actuatable for translating the knife between the retracted and extended positions.
 6. The surgical instrument according to claim 1, further including: a first activation switch configured to selectively energize the electrically-conductive surface of the first jaw member; and a second activation switch configured to selectively energize the electrically-conductive surface of the second jaw member.
 7. The surgical instrument according to claim 1, further including a knife actuation switch configured to selectively energize the knife.
 8. The surgical instrument according to claim 1, wherein the knife and the electrically-conductive surface of at least one of the first and second jaw members are energizable to conduct energy therebetween to electrically cut tissue.
 9. The surgical instrument according to claim 1, wherein the electrically-conductive surfaces of the first and second jaw members are energizable to conduct energy therebetween to seal tissue.
 10. The surgical instrument according to claim 1, wherein the second jaw member is fixed and wherein the first jaw member is movable relative to the second jaw member.
 11. The surgical instrument according to claim 10, wherein the second jaw member defines a knife channel extending longitudinally through an electrically-conductive surface thereof, and wherein, upon translation of the knife from the retracted position to the extended position, the knife is translated at least partially through the knife channel of the second jaw member regardless of whether the first and second jaw members are disposed in the spaced-apart position or the approximated position.
 12. The surgical instrument according to claim 11, wherein the first jaw member defines a knife channel extending longitudinally through an electrically-conductive surface thereof, wherein, upon translation of the knife from the retracted position to the extended position with the first and second jaw members disposed in the approximated position, the knife is translated at least partially through the knife channel of the first jaw member.
 13. The surgical instrument according to claim 12, wherein, upon translation of the knife from the retracted position to the extended position with the first and second jaw members disposed in the spaced-apart position, the knife is spaced-apart from the knife channel of the first jaw member.
 14. The surgical instrument according to claim 13, wherein the knife and the electrically-conductive surface of the second jaw member are energizable to conduct energy therebetween and through tissue to electrically cut tissue via tenting when the first and second jaw members are disposed in the spaced-apart position and the knife is disposed in the extended position.
 15. The surgical instrument according to claim 13, wherein the knife and the electrically-conductive surface of the first jaw member are energizable to conduct energy therebetween and through tissue to electrically cut tissue via scissor-cutting when the knife is disposed in the extended position and the first jaw member moves between the spaced-apart and approximated positions.
 16. The surgical instrument according to claim 13, wherein the knife and the electrically-conductive surface of at least one of the first and second jaw members are energizable to conduct energy therebetween and through tissue to electrically cut tissue when the first and second jaw members are disposed in the approximated position and the knife is translating from the retracted position to the extended position.
 17. The surgical instrument according to claim 1, wherein the knife defines a first tissue-cutting portion configured for use in dynamic tissue cutting and a second tissue-cutting portion configured for use in static tissue cutting.
 18. The surgical instrument according to claim 17, wherein the first tissue-cutting portion of the knife is oriented so as to define a leading end of the knife upon translation of the knife from the retracted position to the extended position.
 19. The surgical instrument according to claim 17, wherein the second tissue-cutting portion is oriented to face the first or second jaw member. 